To prop up is to hold something upright, or to keep it from failing. Prop up the fence.
The figurative sense is nearly always a criticism, since propping up implies the thing should fall. To prop up a failing business with public money is one of the oldest arguments in politics.
1phraseprop upTo hold something upright, or to keep it from failing.
“A single post would prop up the whole wall for another winter.”
prop up is a phrase.
Practised in Phrasal Verbs